Avoiding Voltage-Induced Degradation in PET-ITO-Based Flexible Electrochromic Devices.

The cycling stability of flexible electrochromic devices (ECDs) under humid atmospheres is limited by irreversible indium tin oxide (ITO) reduction. A strategy to limit this degradation was developed and tested for model ECDs based on a sidechain-modified poly(3,4-ethylene dioxythiophene) (PEDOT) derivative and Prussian blue (PB). This work reveals that the cycling stability is reduced by dissolution of the ITO thin films and formation of metallic indium particles on the surface of the ITO layers. The ITO degradation strongly depends on the applied electrode potentials in combination with moisture ingress into the ECDs. To avoid ITO reduction in ECDs, efforts were made to adjust the electrode potentials. ECDs equipped with an auxiliary reference electrode were set up to gather knowledge on the actual electrode potentials. By adjusting the electrode charge density ratio, it was possible to narrow the overall cell voltage window to an extent in which irreversible ITO reduction no longer occurs. Detailed investigation of ECDs with the optimized cell configuration (charge density ratio) showed that the overall device performance with regard to visible light transmittance change and response time is not impaired and that the cycling stability under humid atmosphere (90% rH) is dramatically improved. Thus, the proposed strategy offers an excellent perspective for the commercialization of flexible ECDs upon their enhanced durability.

Neurofilament markers for ALS correlate with extent of upper and lower motor neuron disease.

OBJECTIVE: To determine the diagnostic performance and prognostic value of phosphorylated neurofilament heavy chain (pNfH) and neurofilament light chain (NfL) in CSF as possible biomarkers for amyotrophic lateral sclerosis (ALS) at the diagnostic phase. METHODS: We measured CSF pNfH and NfL concentrations in 220 patients with ALS, 316 neurologic disease controls (DC), and 50 genuine disease mimics (DM) to determine and assess the accuracy of the diagnostic cutoff value for pNfH and NfL and to correlate with other clinical parameters. RESULTS: pNfH was most specific for motor neuron disease (specificity 88.2% [confidence interval (CI) 83.0%-92.3%]). pNfH had the best performance to differentially diagnose patients with ALS from DM with a sensitivity of 90.7% (CI 84.9%-94.8%), a specificity of 88.0% (CI 75.7%-95.5%) and a likelihood ratio of 7.6 (CI 3.6-16.0) at a cutoff of 768 pg/mL. CSF pNfH and NfL levels were significantly lower in slow disease progressors, however, with a poor prognostic performance with respect to the disease progression rate. CSF pNfH and NfL levels increased significantly as function of the number of regions with both upper and lower motor involvement. CONCLUSIONS: In particular, CSF pNfH concentrations show an added value as diagnostic biomarkers for ALS, whereas the prognostic value of pNfH and NfL warrants further investigation. Both pNfH and NfL correlated with the extent of motor neuron degeneration. CLASSIFICATION OF EVIDENCE: This study provides Class II evidence that elevated concentrations of CSF pNfH and NfL can accurately identify patients with ALS.